After more than 5 centuries, the “Castillo San Felipe del Morro” still stands strong. The colossal 18’ thick walls are impressively adorned with cannons, colonial artillery and architecture. In 1961, after enduring wars, pirate attacks and invasions, “El Morro” and its adjacent walls, were declared a World Heritage Site by the United Nations. Today, thousands of tourists and locals visit El Morro. Entrance is only $5 for adults 16 and older, while being free for children.